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<TITLE>Magic-7.3 Command Reference</TITLE>
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<H2>feedback</H2>
<HR>
Query or manipulate feedback entry areas.
<HR>

<H3>Usage:</H3>
   <BLOCKQUOTE>
      <B>feedback</B> <I>option</I> <BR><BR>
      <BLOCKQUOTE>
         where <I>option</I> may be one of the following:
	 <DL>
	   <DT> <B>add</B> <I>text</I> [<I>style</I>] [<I>x1 y1 ...</I>]
	   <DD> Create a new feedback area.  If positions <I>x1 y1 ...</I>
	   	are not specified, then the feedback area created
		corresponds to the area of the cursor box.
	        The feedback entry will be associated with the text
	        <I>text</I>, which will be reported on execution of
	        a <B>feedback why</B> query.  The feedback area will
		be drawn in style <I>style</I>, which may be one of
		the following:
		<UL>
		  <LI><B>dotted</B>
		  <LI><B>medium</B>
		  <LI><B>outline</B>
		  <LI><B>pale</B>
		  <LI><B>solid</B>
		</UL>
		From magic version 7.3.110, <I>any</I> style from
		the ".dstyle" file may be specified (e.g., "yellow1").
		If points <I>x1 y1 ...</I> are specified, then they
		represent a polygonal area for the feedback entry.
		This area may be a point, line, or polygon, and may be
		specified in internal units or metric units.  If the
		feedback area is a point, line, or degenerate polygon
		(polygon with zero internal area), then the <I>style</I>
		must be an outlined style;  otherwise, the style is changed
		to style <B>outline</B> so that the feedback area is
		ensured to be visible.
	   <DT> <B>clear</B> [<I>substring</I>]
	   <DD> Without the argument <I>substring</I>, clears all feedback info.
	   	When <I>substring</I> is specified, only feedback entries
		containing the text <I>substring</I> will be removed.  For
		example, if "cif see CMF" is followed by "cif see CCC", the
		contact cuts will not be seen due to being overlapped by
		the feedback for metal1.  However, if this is followed by
		"feedback clear CMF", the feedback area for metal1 will
		be removed, leaving the contact cuts visible.
	   <DT> <B>count</B>
	   <DD> Count the number of feedback entries
	   <DT> <B>find</B> [<I>nth</I>]
	   <DD> Put the cursor box over next (or <I>nth</I>) entry
	   <DT> <B>help</B>
	   <DD> Print help information
	   <DT> <B>save</B> <I>file</I>
	   <DD> Save feedback area information into file <I>file</I>
	   <DT> <B>why</B>
	   <DD> Print text associated with all feedback areas under
		the cursor box.
	 </DL>
      </BLOCKQUOTE>
   </BLOCKQUOTE>

<H3>Summary:</H3>
   <BLOCKQUOTE>
      The <B>feedback</B> command queries or manipulates feedback
      areas, which are areas drawn on top of the layout and may
      be used for annotations and markers.  Internally, <B>magic</B>
      uses feedback areas to report CIF/GDS layers (<B>cif see</B>
      command), and errors generated by the <B>extract</B> command.
      CIF/GDS feedback is placed on the output (usually centimicron)
      grid, which cannot be done with the <B>feedback add</B>
      command directly from the command-line.
      <P>
      
      Feedback information and areas are not saved in the layout
      file. <P>
   </BLOCKQUOTE>

<H3>Implementation Notes:</H3>
   <BLOCKQUOTE>
      <B>feedback</B> is implemented as a built-in <B>magic</B> command.
   </BLOCKQUOTE>

<H3>Bugs:</H3>
   <BLOCKQUOTE>
      Small feedback areas were previously drawn solid to prevent them
      from disappearing entirely;  however, this created bizarre results
      in CIF/GDS feedback when several narrow feedback areas are tiled
      together, so it was removed.  This leaves the possibility that
      feedback areas smaller than the spacing between feedback
      crosshatch lines might not be drawn;  an inconvenience, but
      not a serious problem.<P>

      There should be a mechanism for removing only the feedback entries
      under the cursor box, or the current feedback entry. <P>
   </BLOCKQUOTE>


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<P><I>Last updated:</I> December 4, 2005 at 8:32pm <P>
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